Vibrational mode shifts as a measure of local strain in the dilute nitride semiconductor alloy GaNx As1-x

The effect of an applied strain on the frequency of the localized vibrational mode associated with substitutional nitrogen in the dilute nitride GaNx As1-x is calculated within first-principles density-functional theory, using a supercell approach. Calculated values of the deformation potentials of frequency of the localized nitrogen vibration mode for each irreducible component of the local strain are as follows: (Γ1 representation) a=-1907 cm-1, (Γ3 representation) b=22 cm-1, (Γ4 representation) d=-741 cm-1.